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I have a Panamax surge protection strip. It has 2 coax inputs & outputs labeled SAT which I have used for my T-60 & now my HD TIVO. I am running two new RG6 lines to keep my T-60 in the mix. The surge protector also has 2 inputs & outputs that are labeled cable.

Can I hook the T-60 up to the "cable" coax surge protectors? Is there really any difference or is it just labeling?

You can certainly use them, but they do attenuate the signal somewhat. More importantly, what is the point? Other than a direct hit on your dish from a lightning strike that will fry your Panamax and everything connected to it, there is virtually no possibility of a surge coming down the line from your dish. Cable signals DO need surge protection, since inductive surges can and do travel long distances down the coaxial cable.

I use the coax filters on my monster surge protectors on the 4 lines from my dish before going to my 4 x 8 switch. The lines run past the electric meters for my condo building to get to the grounding block. then run back by the electric meters again to get to my 4 x 8 switch in my living room. Without the coax filters I get a wavy lines on the TVs. This disappears when connected to the coax protection.

It is grounded but because of those electric lines I get interference in the lines. This is because of the crappy company MASTECH. I won't let them anywhere near my equipment again. especially after they mounted the dish and they couldn't figure out why I wasn't able to get all 3 sats. Well the building next door was inthe way. I moved the dish over a few feet a remounted the pole and did a better job in 1 hour than they did working on it for 4 hours. They tried to tell me that I was in the only location that couldn't receive the signals from all 3 sats because of my location on earth.
MASTECH is a bunch of crooks. Never use MASTECH!!

It is possible for a nearby lightning strike to jump to the cables coming from the sat dish. Obviously a direct hit to the sat dish will potential fry evrything downstream including your house. But I think it certainly worth protecting all incomming wires and cables via surge protection.

quote:Originally posted by aaronwt I use the coax filters on my monster surge protectors on the 4 lines from my dish before going to my 4 x 8 switch. The lines run past the electric meters for my condo building to get to the grounding block. then run back by the electric meters again to get to my 4 x 8 switch in my living room. Without the coax filters I get a wavy lines on the TVs. This disappears when connected to the coax protection.

Obviously, YRMV, but I wasn't aware that a surge protector could filter out video noise. That isn't what they are designed to do. Even though the coax is going to a ground block, it may be that it isn't actually being grounded there, but gets it's ground at the surge protector.

The way you have wired your system, with the coax passing through an ungrounded multiswitch on its way to the grounding block, you may have created a ground loop which is actually causing the video noise.

The switch is grounded. The cable is the dual RG6 with a ground wire in the middle. This ground is connected to the switch and the grounding rod for the building(where the telephone and CATV are grounded) Before I had the 4 x 8 switch inside, I just used the four outputs from the switch on the dish. The interference definitely comes from the cables runnning by the main power lines. I tested this by running lines straight from the dish through a window and I didn't have any problems. I then used those cables and ran them behind the conduit for the meters outside(where the buried cable is)Once i did that I had the same interference on screen. Only when I ran it through the protected coaxial connections on the Moster Surge protector, did the interference disappear.

It is electrical interference. I spent some time trouble shooting the problem. The only way to resolve it was to either avoid running the cables by the electric meters or running the cables through the coax protector. those were the only two things that solved it. When i say interference, I mean there was a line or 3 moving up the screen, a disturbance to the picture, the same thing you get with electrical disturbance on the line. I tried this with receivers in different locations, also having things plugged into different circuits. The results were the same. The only the common to the disturbance was the electric meters. take that out of teh equation and the lines are gone. Since I can't take that out of the equation, my only alternative is the coax surge protector. This has worked without any negative results fro 2.5 years now.
Would I rather have the lines run a different way, yes I would. But that crappy company MASTEC ran them right behind the electric meters. Another reason on a long list that I never want anyone from MASTEC near my equipment ever again. And this was 2.5 years ago. Everytime I think about all the time I wasted with that crappy company(MASTEC) I get furious. DirecTV gave me some credits but it didn't even come close to compensating me for all the time I wasted with them. i had to remount the disgh myself, a few feet away, since those idiots couldn't figure out that the buiding next door was obscuring the signal.

quote:Originally posted by aaronwt The switch is grounded. The cable is the dual RG6 with a ground wire in the middle. This ground is connected to the switch and the grounding rod for the building(where the telephone and CATV are grounded) Before I had the 4 x 8 switch inside, I just used the four outputs from the switch on the dish. The interference definitely comes from the cables runnning by the main power lines. I tested this by running lines straight from the dish through a window and I didn't have any problems. I then used those cables and ran them behind the conduit for the meters outside(where the buried cable is)Once i did that I had the same interference on screen. Only when I ran it through the protected coaxial connections on the Moster Surge protector, did the interference disappear.

How did you ground your multiswitch? Where did you tie in to the building's system ground? Is the CATV system's ground rod BONDED to the building's ground bus? If it isn't grounded at the same point as your coax, you can easily get a ground loop. (I've seen CATV systems using a ground that isn't bonded to the building's main ground bus, and the same symptoms you describe have resulted.)

Typically, for most multiple dwelling buildings, the system ground is tied to the water main. (If you see a large guage wire jumpering the water meter, that is the case.) You can have other grounding points such as ground rods, but if they aren't bonded to the system ground, you almost certainly will generate a ground loop.

If the main service entrance is generating the noise, it is a 60 hz sine wave causing the problem. This is virtually impossible to filter out, and certainly a surge protector won't do it. My RG-6 is bonded to my system ground right in my service entrance panel. There is no noise whatever, and I don't run the cables through any surge limiting device whatever, even though I do have one for telephone and power lines for my system.

I'm not saying you didn't observe what you say you did. What I am strongly suggesting is that the circuitry inside your Panamax has nothing to do with curing the problem, and that you probably would observe the same result if you simply grounded the coax cable and all your equipment at any single point that is tied to the system ground. Your Panamax is grounded to your system through the grounded outlet at your wall, and in my view, that is the only reason the Panamax solves your noise problem.

What your Panamax is doing is, in effect, bonding the CATV ground rod to your system ground by way of your wall outlet. The wall outlet ground is bonded to the ground bus in your apartment's subpanel in your apartment, and that ground bus is bonded to the ground at the service entrance of the building, thereby eliminating the ground loop's effect on your TV. This scenario is symptomatic of an unbonded CATV ground rod.

I don't believe there is any way your Panamax surge protector could possibly filter out a 60 hz ground loop, and there is likewise no way the electrical service equipment could generate any other spurious signal in your coax lines but 60 hz.

I am ground to the exact same spot that the electric meters are grounded, the Telphone lines are grounded and the cable company is grounded. The wire runs from the coax grounding block to the wire from the grounding rod where everything else for the building is grounded.(Everything is in the same location) I also grounded my 2 OTA antennas(2 squareshooters) in the same spot as well.

quote:Originally posted by aaronwt I am ground to the exact same spot that the electric meters are grounded, the Telphone lines are grounded and the cable company is grounded. The wire runs from the coax grounding block to the wire from the grounding rod where everything else for the building is grounded.(Everything is in the same location) I also grounded my 2 OTA antennas(2 squareshooters) in the same spot as well.

If what you say is true, then can you explain why the CATV system is not subject to the same video noise you evidently are experiencing.

I still say that from the symptoms you describe, you have a ground loop. It's easy to see if that is the case. Just connect a polarized 2 wire extension cord to your surge protector, leaving the ground unused. Then connect a milliameter between the surge protector and the ground at the wall receptacle. There should be no measurable current flowing. If any current at all is flowing you have one of two things going on: Either a ground fault (not good) or a ground loop (also not good). A ground fault receptacle is supposed to trip at 5 milliamperes, which is a lot of current to be flowing through the ground--enough to be dangerous. I doubt that would be the case.

But something on the order of .1 millivolt certainly is strong evidence for a ground loop. And if you have that kind of reading, your coax does not have a good ground.

You may not care enough to check it out, but clearly there is something amiss with your ground, somewhere in the system. 60 hz A/C at line voltage will not induce noise in a properly grounded system. What do you think the shielding is for? If it were just to provide a ground, we would still be using 300 ohm twin lead.

Ive seen it myself many times. Just the fact that you are grounded to a ground rod is a red flag for me. Is there no ground coming in on the power drop? Try grounding directly to the power meter. I think you'll see he is right. Coax is far less susceptible to power interference than twisted pair and other forms of media transmission.
If they ran your lines right in front of the power meter then why not ground there and do it right? Why go to all of the trouble of running the ground wire to the ground rod?
Maybe a picture would give us a better idea of what you are talking about.

quote:Originally posted by UTmatt20 Ive seen it myself many times. Just the fact that you are grounded to a ground rod is a red flag for me. Is there no ground coming in on the power drop? Try grounding directly to the power meter. I think you'll see he is right. Coax is far less susceptible to power interference than twisted pair and other forms of media transmission.
If they ran your lines right in front of the power meter then why not ground there and do it right? Why go to all of the trouble of running the ground wire to the ground rod?
Maybe a picture would give us a better idea of what you are talking about.

It is grounded by the power meters. All the utilites are in the same location(within 3 feet) The meters are using the same grounding rod as the other utilites. I am connected to the same grounding rod.

Anyway it's been like this for 2.5 years and I don't have any problems, so I see no need to change it now.

I had my sat installed in the back of my house and grounded to a ground rod (the power meter is the far side of the house.)

I then ran the 4 wires into my house where they connected to a ground blcok, which then connected to 4 runs which ran to different rooms in my house. 2 of these ran to my hd tivo. Both of these ran through a panamax max with sat protection.

I had a close lightning strike or severe surge which must have jumped the coax made it through everything and fried my hd tivo. I put my zenith 520 back there and found that my satellite too had been fried. I received a new satellite and have now found that all 4 lines running from my satellite to the ground block are fried. I will test the 4 runs that were coming from the ground rod to the receiver but i fear the worse here as well.

Argh, i mean what are the odds of losing all my coaxial lines throughout my house. Nothing else was damaged.